Long-range chain orientation in 1-D co-ordination polymers as a function of anions and intermolecular aromatic interactions

Two novel grid networks based on Keggin-type polyoxometalate clusters assembled through weak Cu⋯O interactions

“…Water molecules and all hydrogen atoms are omitted for clarity. of compound 1 show the characteristic g i > 2.1 > g^> 2.0, and is consistent with their crystal structure which possesses five-coordinate square pyramidal CuN 4 O cores, where four near planar ligands bind to Cu(Õ) ion with one weakly bound axial ligand, namely Cu(1)-O (8).…”

“…The main structural feature of 1 is that the Keggin unit acts as a ligand toward the Cu(II) atom through a terminal oxygen [O (8)] with weak coordination interaction, different from that of polyoxianion unit linked transition metals with strong coordination interaction or only electrostatic interaction in previous literature [18]. To the best of our knowledge, organic or transition metal complex moieties supported by Keggin unit by such ways have not been reported to date.…”

“…To the best of our knowledge, organic or transition metal complex moieties supported by Keggin unit by such ways have not been reported to date. The Cu(1) atom in polyoxoanion framework is defined by four nitrogen donors from two 2,2 0 -bipyridine ligands and a terminal oxygen from the Keggin skeleton with the distances Cu(1)-N 1.954(7)-1.989 (8) and…”

“…One of the important targets in the preparation of hybrid materials is to establish the possible connections between organic and/or inorganic molecular fragments on the basis of various forces including strong and directional interactions [6] (e.g. metal-ligand coordination) and weak interactions such as hydrogen-bonding [7], p-p stacking [8], CNÁ Á Áp interaction [9], weak coordination interaction [10], SÁ Á ÁX (X = O, S, N, etc.) interactions [11], halogen-halogen [12], AgÁ Á ÁX (X = Ag, O, S) interactions [13], and so on.…”

Two copper(II) complexes containing the common chain structures with different charge states

“…Furthermore, high tendency of the pyrimidinedicarboxylate to adopt chelating coordination through the endocyclic nitrogen atom and the carboxylate oxygen atom may also play a role in facilitating the formation of common topological structures. More remarkably, the presence of free [Cu(NH 3 ) 4 (H 2 O)] 2+ unit has only a slight influence on the packing arrangement of the 1D chains, which is different from the usual observations that the shapes and packing states of chains easily undergo variation in response to different guest molecules or counterions [17][18][19]. (Fig.…”